This invention relates to insulation displacement connectors, and more specifically relates to insulation displacement connectors which can make connection to the wires of flat multiwire cable which are very closely spaced, for example by 0.033 inch.
Insulation displacement connectors are known for making connection to flat multiwire cable. The usual contact orientation in a header and/or a mating socket is 30 contacts on two rows making a 60 contact connector; or 25 contacts on each of two rows making a 50 conductor connector; or 2 rows of 13 contacts making a 26 contact header and/or connector.
Commonly, insulation displacement connectors can engage wires spaced from one another within the cable by about 0.50 inch. If, however, the wires are even more closely spaced, it is difficult to provide a connector which is relatively inexpensive since the individual connector contacts have different geometries.
In accordance with one aspect of the present invention, a third row of contacts is added so that a 60 conductor header and/or socket has 3 rows of 20 contacts. A 24 contact device would have 3 rows of 8 contacts. To accomplish this, a novel single contact is employed. The novel contact of the invention uses one and the same physically shaped contact to connect electrically and mechanically from conductors on 0.033 inch centers to electrical contacts on 0.100 inch centers. Single contact usable in all positions consists of an IDC tail that interfaces with cable conductors on 0.033 inch centers; noses whose centers are spaced 0.033 inch from each other; and a metal conductor connecting each end. The center line of one nose shares the same center line as IDC tail. The other nose center line is offset by 0.033 inch from center line of IDC tail. Consequently, contact can be made to multi-cable wires as closely spaced as 0.033 inch, while using identical contacts for the insulation displacement connector.
More particularly, in accordance with the invention, the novel contact structure has a contact insulation piercing end which is laterally displaced from the lateral central line of the contact by a distance equal to one-half the distance between adjacent wires in the multicable conductor. By then using the same contact, but rotating the contacts of adjacent rows of contacts which are vertically aligned relative to one another, the contact insulation piercing ends of the contacts will be displaced by the requisite distance to engage adjacent wires in the cable.
The so-called nose ends of the contact, which are the ends which engage the pins of headers, extend through the housing of the connector and terminate at a location where they can slidingly engage the pins of a conventional header. The nose ends of the contacts are bowed springs which are disposed in a generally flat plane which is generally coplanar with the plane of the contact tine. The nose ends are sufficiently wide that they will engage the header pin at the header pin location regardless of the angular position of the contact within the housing. The header pin engages one lateral side of nose end where the contact has one angular orientation. Pins of other rows can engage the other lateral side of the contacts of that row. Preferably, the nose end is bifurcated into two legs to ensure a high-pressure contact from one of the legs to a header pin regardless of the lateral position of the header pin with respect to the contact nose.
A third row of contacts is preferably provided where the openings in the housing for the third row of contacts are laterally displaced from the other openings by the distance of the spacing between adjacent wires in the cable which is to be received by the insulation displacement connector. The insulation piercing ends of each of the contacts of each of the three rows of the insulation displacement header will then be spaced from one another by the spacing of the wires along the full length of the header to place a wire piercing end of a contact in alignment with each wire of a header. The nose end of the contacts in the third row is operable to receive a plug-in contact which is in line with the contacts of two upper rows. Thus, one lateral row of plug-in contacts can connect to three cable conductors spaced from one another by 0.033 inch. A second line of three plug-in contacts are connected to the next three cable conductors, also spaced from one another by 0.033 inch.